IPE use; Edge Grain vs Flat grain

[BEN]

Guys,

I got an 8' Ipe 4x4 that I'm going to cut into slats for making  bamboo backed bows. Is there a tillering difference or difference in thickness neeeded when using quarter-sawn wood grain VS using a flat-grain board?
On another post I asked about IPE, I was told that 5/8-1" when using boards-----I'm assuming that is with a flat grain. Is there a difference when using quarter-sawn grain? I just want to get in the ballpark before cutting this thing down......thanks

Ben

[Jesse Peltan]

I think you need edge grain if you don't have glass on the bow, but I am not sure.

[Art B]

There won't be any difference in thickness Ben. On the last two Ipes bows I made I used the quarter-sawn and I had some serious grain problems. The quarter-sawn grain keep popping up the inner two-thirds of both limbs. Fixed that with a belly veneer of flat-sawn Ipe but needless to say, I won't be using quarter-sawn Ipe anymore.

ART B

[Springbuck]

Ipe is seriously dense, I doubt you'll see much difference.  With backed bows, grain orientation  matters little as long as the grain runs strongly lengthwise to the bow and doesn't run off sharply.  I would bet that Art's grain was angling off, but was hard to see since it was quartersaw.  Ipe grain can be hard to see as it is, esp. if it's dark colored.

  Actually a 5/8" thick slat, plus a backing, is enough to make a s stiff a bow as a mortal man can shoot...I've had a 68" long, 3/8" thick ipe lam and 1/8" max thickness bamboo backing, 1 1/2" wide come out well into the 60's at 29".

[BEN]

"Springbuck"-----I've got some slats drying right now. 2 @ 5/8 and 2 @ 1/2. I'm gonna see what happens with these before I cut the rest out.
I'm aiming for a slender limb bow---no more than 1 1/4" wide at the fades and going down to 3/8 -1/2 at the tips.

thanks for the help guys

ben